The Portuguese forward was accused in September of sexually assaulting American woman Kathryn Mayorga in a hotel room in Las Vegas in June 2009 – a claim he denied.

Ronaldo, 33, said rape was “an abominable crime that goes against everything that I am and believe in”.

Lawyer Peter S Christiansen has confirmed that investigators are seeking DNA from the Juventus star, but did not confirm a Wall Street Journal report that a warrant was sent to Italy to get Ronaldo to submit a sample.

Police in Las Vegas declined to comment on the investigation, which was originally closed in 2009 but reopened days before Ms Mayorga filed a civil lawsuit in September.

Nike, which has had a contract with Ronaldo since 2003, said at the time it was “deeply concerned by the disturbing allegations” and would “continue to closely monitor the situation”.

The former Manchester United winger – who Juventus signed Real Madrid for €112m (£99.2m) last summer – dismissed the claims as “fake news” before issuing a full and official denial.

“Keen as I may be to clear my name, I refuse to feed the media spectacle created by people seeking to promote themselves at my expense,” he said.

“My clear conscious will thereby allow me to await with tranquillity the results of any and all investigations.”

The lawsuit against him claims teacher Ms Mayorga was coerced into signing a $375,000 (£332,000) out-of-court settlement with Ronaldo in 2010.

She said she wanted the agreement to be declared void, explaining that she had gained the courage to speak out because of the #MeToo movement.